I have Outlook on 3 laptops via Office 365. On only one of the computers, when I open Outlook a small screen opens asking for me to verify my phone number, including Country Code. I have only two phone numbers, one for my landline and one for my cell. Inputing either is unrecognized by Outlook and I get a "not the correct number" message. The other two computers do not request the phone number. The Outlook symbol on my Task Bar shows a triangle with an exclamation point in it and Outlook on this computer does not update from either of the other two. Any ideas???